KR200370456Y1 - Fluid Pressure Cylinder - Google Patents

Abstract

The present invention relates to a hydraulic cylinder, the first valve housing 61 of the check valve 60 for the front cylinder chamber for controlling the flow of the fluid supplied to the front and rear cylinder chambers (33a, 33b) of the hydraulic cylinder is inside The first fluid passage (61a) is formed to connect the fifth fluid supply discharge path (34) to the front cylinder chamber (33a), the end of the cylinder body member through the piston plate 42 of the piston member (40) And a first guide protrusion (63) protruding with a predetermined length to be coupled to the inner side of the (50), and the second valve housing (71) of the check valve (70) for the rear cylinder chamber has a sixth fluid therein. A second fluid passage 71a which connects the fluid supply discharge passage 35 to the rear cylinder chamber 33b is formed, and an end thereof passes through the piston plate 42 of the piston member 40 so that the cylinder body member 50 is formed. A second guide protrusion protruding with a predetermined length to be coupled to an inner side of the (73), the two guide protrusions 73, the cylinder chamber 33 overpressured by communicating the previous, rear cylinder chambers 33a, 33b when overpressure occurs in the front and rear cylinder chambers 33a, 33b. By reducing the pressure of the pressure reducing means 100 is provided, the front and rear reciprocating motion of the piston member 40 is guided by the first and second guide protrusions 63 and 73 to separate the guide pin into the cylinder body or It is not necessary to install on the piston plate 42.

In addition, the second valve housing 71 of the check valve 70 for the rear cylinder chamber is integrally provided with a pressure reducing means 100 for reducing the overpressure generated in the rear cylinder chambers 33a and 33b before the hydraulic cylinder is operated. It is not necessary to attach a separate pressure reducing valve (relief valve) to the piston plate 42.

Therefore, by reducing the number of parts installed or installed in the hydraulic cylinder to enable a compact design of the hydraulic cylinder, as well as to reduce the manufacturing cost, it is a very useful design that can increase the assembly during manufacturing.

Description

Hydraulic Cylinder {Fluid Pressure Cylinder}

The present invention relates to a hydraulic cylinder, and more particularly, to a compact design by improving a structure of a check valve for supplying and discharging a fluid in a predetermined direction into a cylinder chamber of a hydraulic cylinder.

Generally, a hydraulic cylinder drives a chuck attached to a main shaft of a machine tool, such as a lathe, to be gripped or released, and is a mechanism that is operated at the pressure of a fluid supplied into the cylinder chamber.

As shown in FIG. 1, the hydraulic cylinder is generally formed with a through part 11 penetrated to a predetermined size from one side to the other side of the body, and fluid flows into and out of the through part 11 from the outside of the body. A cylinder housing 10 in which first and second fluid supply discharge passages 12 and 13 are formed;

The coupling portion 21 penetrates from one side to the other side inside the body, and a bearing 22 is provided inside the coupling portion 21, and the first coupling portion is formed inside the coupling portion 21 from the outside of the body. A sleeve member 20 having third and fourth fluid supply discharge paths 23 and 24 associated with the two fluid supply discharge paths 12 and 13;

One side is composed of a valve rod 31 coupled to the engaging portion 21 of the sleeve member 20, the other side is composed of a valve plate 32 located on the front of the cylinder housing 10, the valve plate ( 32) Fifth and sixth fluid supply discharge paths 34 which form a cylinder chamber 33 on the front side and connect the third and fourth fluid supply discharge paths 23 and 24 to the cylinder chamber 33 therein. 35 is provided with a rotary valve member 30;

The body is composed of a piston rod 41 coupled to the valve rod 31 having a predetermined length and sliding forward and backward, and the cylinder cylinder 33 on the outer circumferential surface of the piston rod 41, the front and rear cylinders A piston member (40) protruding from the piston plate (42) for partitioning and sealing the seals (33a, 33b);

It is mounted on the valve plate 32 front surface of the rotary valve member 30 to form and seal the cylinder chamber 33 partitioned into the front and rear cylinder chambers 33a and 33b by the piston plate 42 therein. A cylinder body member (50) having a seventh fluid supply discharge path (51) formed at one side thereof to connect the fifth fluid supply discharge path (34) to the front cylinder chamber (33a);

The front cylinder chamber 33a is mounted on the sixth fluid supply discharge path 35 into the rotary valve member 30 through the sixth fluid supply discharge path 35 and the seventh fluid supply discharge path 51. Check valve 70 for the front cylinder chamber for controlling the flow of the fluid supplied to, discharged in a predetermined direction;

Mounted on the fifth fluid supply discharge path 34 into the rotary valve member 30, the flow of fluid supplied to and discharged from the rear cylinder chamber 33b through the fifth fluid supply discharge path 34 is discharged. It consists of a check valve 60 for the rear cylinder chamber to control in a constant direction.

That is, the piston member 40 reciprocates forward and backward by supplying fluid to the cylinder chamber on one side of the front and rear cylinder chambers 33a and 33b and discharging the fluid inside the cylinder chamber on the other side. The jaw of the chuck connected to the piston rod 41 is gripped or released by the reciprocating motion of the piston member 40.

Meanwhile, the front and rear cylinder chamber check valves 60 and 70 may include a valve housing 80 having a fluid passage 81 through which fluid passes;

The fluid passage (80) is elastically supported by the spring member (83) in the fluid passage (81) of the valve housing (80) to block the fluid passage (81). A steel ball 82 for opening 81;

It is composed of a pilot spool 84 is coupled to one side of the valve housing 80 when the fluid is supplied to the opposite check valve is moved by the pressure of the supplied fluid to push the steel ball 82 to open the fluid passage .

That is, when the fluid is supplied to the front and rear cylinder chamber check valves 60 and 70 at a predetermined pressure or more, the fluid passage 81 is opened to supply or discharge the fluid to the cylinder chamber 33, and the power outage. When the power supply of the machine tool is turned off by the same external factor and the supply of hydraulic pressure is cut off during operation, the steel ball 82 returns to its original position by the elastic restoring force of the spring member 83 and blocks the fluid passage 81 so that the cylinder chamber ( 33) Prevents the chuck from releasing the workpiece by preventing the fluid filled inside from discharging to the outside.

In the piston plate 42 of the piston member 40, when overpressure occurs in the front and rear cylinder chambers 33a and 33b partitioned by the piston plate 42, the front and rear cylinder chambers 33a and 33b are formed. The relief valve 90 for reducing the pressure of the cylinder chamber over-pressure by communicating with is provided.

In addition, both ends of the piston member 40 are coupled to the guide pins 91 fixed to the cylinder body member 50 and the rotary valve member 30, respectively. It is guided by, and it moves smoothly in the state which sealed the front cylinder chamber 33a, 33b.

However, the above-described conventional hydraulic cylinder has a check valve for the front and rear cylinder chambers for supplying and discharging the fluid in a predetermined direction to the inside of the cylinder chamber, and a relief to reduce the overpressure when overpressure is generated in the front and rear cylinder chambers. Since the valves are manufactured separately and installed separately, the entire length of the hydraulic cylinder was long due to the respective installation spaces.

In addition, a separate guide bar to guide the reciprocating motion of the piston member moving back and forth by the hydraulic pressure supplied, discharged to the cylinder chamber has to be provided to increase the labor and manufacturing cost during manufacturing.

Therefore, a design in which the size of the hydraulic cylinder becomes smaller than a certain limit is impossible, and there is a complicated end of the structure and design of the hydraulic cylinder.

In addition, the cylinder body member has a fluid supply discharge path for supplying and discharging the fluid to the front cylinder chamber, so that the rigidity of the side where the fluid supply discharge path is formed is weaker than that of other parts, so that the closed end is easily broken during use.

It is an object of the present invention to provide a hydraulic cylinder that enables a compact design with a smaller body length than a conventional hydraulic cylinder by simplifying the structure of the hydraulic cylinder by integrally forming a relief valve on the check valve of the hydraulic cylinder.

An object of the present invention is to provide a hydraulic cylinder that can increase the economics and assembly and durability in manufacturing by reducing the number of parts.

1 is a cross-sectional view showing the internal configuration of a conventional hydraulic cylinder.

Figure 2 is an overall perspective view showing the external shape of the hydraulic cylinder of the present invention.

Figure 3 is a cross-sectional view showing the internal configuration of the hydraulic cylinder of the present invention.

Figure 4 is a cross-sectional view showing a check valve for the front cylinder chamber of the present invention.

5 is a cross-sectional view showing a check valve for the rear cylinder chamber of the present invention.

6 is a cross-sectional view of the hydraulic cylinder of the present invention in use.

* Description of the major symbols in the drawings *

10-cylinder housing 11-penetration

12-First fluid supply outlet 13-Second fluid supply outlet

20-sleeve member 21-coupling part

22-Bearing 23-Third fluid supply outlet

24-4th fluid supply outlet 30-Rotary valve member

31-valve rod 32-valve plate

33-Cylinder Room 34-Fifth Fluid Supply Drain

35-6th fluid supply discharge passage 40-piston member

41-Piston Rod 42-Piston Plate

50-cylinder body member 60-check valve for front cylinder chamber

61-1st valve housing 62-1st shut-off means

63-1st guide protrusion 70-Check valve for rear cylinder chamber

71-2nd valve housing 72-2nd shutoff means

73-second guide projection 100-decompression means

110-1st cylinder room connecting passage 111-3rd coil spring

112-3rd ball member 120-2nd cylinder chamber connection passage

121-4th coil spring 122-4th ball member

The purpose of the present invention is the first and second fluid supply discharge path is formed in which the through part 11 is penetrated to a predetermined size from one side to the other side and the fluid is introduced into and discharged from the outside of the body into the through part 11. A cylinder housing (10) in which (12, 13) are formed;

Coupling portion 21 is formed through the inner side of the body from one side to the other side, the third body connected to the first, second fluid supply discharge passage (12, 13) from the outside of the body to the inside of the coupling portion 21 A sleeve member 20 having four fluid supply discharge paths 23 and 24 formed therein and fixedly coupled to the through part 11 of the cylinder housing 10;

One side is composed of a valve rod 31 coupled to the engaging portion 21 of the sleeve member 20, the other side is composed of a valve plate 32 located on the front of the cylinder housing 10, the valve plate ( 32) Fifth and sixth fluid supply discharge paths 34, which form a cylinder chamber 33 in front, and connect the third and fourth fluid supply discharge paths 23 and 24 to the cylinder chamber 33 therein. A rotary valve member 30 formed with 35;

The body is composed of a piston rod 41 coupled to the valve rod 31 having a predetermined length and sliding forward and backward, and the cylinder cylinder 33 on the outer circumferential surface of the piston rod 41, the front and rear cylinders A piston member (40) protruding from the piston plate (42) for partitioning and sealing the seals (33a, 33b);

It is mounted on the valve plate 32 front of the rotary valve member 30 to supply fluid therein and forms a cylinder chamber 33 partitioned into the front and rear cylinder chambers 33a and 33b by the piston plate 42. A cylinder body member 50 which seals the cylinder chamber 33;

The first fluid passage 61a is opened only when the fluid is supplied to the inside of the first valve housing 61 having the first fluid passage 61a communicating with the fifth fluid supply discharge passage 34. A first shut-off means (62) and a check valve (60) for the front cylinder chamber mounted on the fifth fluid supply discharge path (34) inside the rotary valve member (30);

The second fluid passage 71a is opened only when the fluid is supplied above a predetermined pressure in the second valve housing 71 in which the second fluid passage 71a communicating with the sixth fluid supply discharge passage 35 is formed. In the configuration of the check valve 70 for the rear cylinder chamber is provided with a second blocking means 72 is mounted on the sixth fluid supply discharge path 35 into the rotary valve member 30,

The first valve housing 61 of the check valve 60 for the front cylinder chamber is formed with a first fluid passage 61a for connecting the fifth fluid supply discharge passage 34 to the front cylinder chamber 33a. It has a first guide protrusion (63) protruding with a predetermined length so that the end portion penetrates through the piston plate (42) of the piston member (40) and is coupled to the inner surface of the cylinder body member (50). The second valve housing 71 of the check valve 70 has a second fluid passage 71a which connects the sixth fluid fluid supply discharge passage 35 to the rear cylinder chamber 33b, and has an end portion of the piston. And a second guide protrusion 73 extending through the piston plate 42 of the member 40 and having a predetermined length so as to be coupled to the inner surface of the cylinder body member 50. The second guide protrusion 73 If overpressure occurs in the front and rear cylinder chambers 33a and 33b, the front and rear cylinder chambers 33a, This is achieved by providing a decompression means 100 which communicates 33b) with each other to reduce the pressure in the overpressured cylinder chamber 33.

That is, the first and second valve housings 61 and 71 of the check valves 60 and 70 for the front and rear cylinder chambers are coupled to the inner surface of the cylinder body member 50 by passing through the piston plate 42 to form a piston member ( It serves as a guider to guide the reciprocating motion of 40).

In addition, when overpressure is generated in each cylinder chamber 33 during the operation of the machine tool, the pressure reducing means 100 for reducing the overpressure is provided in the second valve housing 71, so that a separate relief valve is provided in the cylinder chamber ( 33) There is no need to install it inside.

Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is an overall perspective view showing the external shape of the hydraulic cylinder of the present invention.

3 is a cross-sectional view showing the internal configuration of the hydraulic cylinder of the present invention, showing a state in which the piston member is retracted.

4 is a cross-sectional view showing a check valve for a front cylinder chamber of the present invention, in which a second fluid passage is formed in an interior of a second valve housing to an end of the second valve housing.

FIG. 5 is a cross-sectional view showing a check valve for a rear cylinder chamber of the present invention, which shows that the pressure reducing means is opened inside the first valve housing when the overpressure occurs in the front and rear cylinder chambers.

Figure 6 is a cross-sectional view of the operating state of the hydraulic cylinder of the present invention, showing that the piston member is moved back and forth to operate.

Hereinafter, as shown in FIGS. 2 to 3, the cylinder housing 10 of the hydraulic cylinder according to the present invention has a through portion 11 penetrated to a predetermined size from one side of the body to a predetermined size, and the fluid inside the body. First and second hydraulic ports (10a, 10b) for introducing and discharging to the drain and the drain port (10c) for discharging the introduced fluid to the outside is provided.

The hydraulic cylinder has first and second fluid supply discharge paths 12 and 13 for supplying and discharging fluid from the outside of the body to the inside of the through part 11, and the first fluid supply discharge path 12 is formed in the first and second fluid supply discharge paths 12. The 1st hydraulic port 10a and the 2nd fluid supply discharge path 13 are respectively connected to the 2nd hydraulic port 10b.

The sleeve member 20 is coupled to and fixed to the penetrating portion 11 of the cylinder housing 10, and the coupling portion 21 penetrates from one side to the other side inside the body.

Both ends of the sleeve member 20 are installed at both ends of the sleeve 22 so that the bearings 22 are coincident with the inner surface of the coupling portion 21, and the first and second fluid supply discharges are disposed between the bearings 22, respectively. In the furnaces 12 and 13, third and fourth fluid supply discharge passages 23 and 24 are formed which are connected to the inside of the coupling portion 21.

In addition, the rotary valve member 30 is coupled to the coupling portion 21 of the sleeve member 20 so that the rotary valve member 30 is smoothly rotated by the bearing 22 when the workpiece bitten by the chuck of the machine tool rotates. do.

The rotary valve member 30 has a predetermined length and a moving insert portion 30a is formed in which the piston member 40 to be described later is slidably moved forward and backward to form a coupling portion of the sleeve member 20 ( A valve rod 31 coupled to 21; The valve rod 31 is protruded with a predetermined thickness and positioned at the front of the cylinder housing 10 so as to be coupled to the cylinder housing 10 with a labyrinth type sealing structure. The valve plate 32 is formed.

In addition, the fifth and sixth fluid supply discharge paths 34 and 35 are formed inside the rotary valve member 30 to connect the third and fourth fluid supply discharge paths 23 and 24 to the cylinder chamber 33. do.

In addition, a second pilot spool of the rear cylinder chamber check valve 70 mounted in the sixth fluid supply discharge path 35 in connection with the third fluid supply discharge path 23 in the rotary valve member 30 ( The first fluid pressure passage 34a for guiding the fluid to pressurize 75, and the check valve for the front cylinder chamber attached to the fifth fluid supply discharge passage 34 in association with the fourth fluid supply discharge passage 24. A second fluid pressure passage 35a for guiding the fluid to pressurize the first pilot spool 65 of 60 is formed. The third and fourth fluid supply discharges are formed on the inner surface of the sleeve member 20. A plurality of first fluid movement holes (not shown) communicating with the furnaces 23 and 24 are formed, respectively, and the outer peripheral surface of the rotary valve member 30 is formed at a position corresponding to the first fluid movement hole. Along the fifth and sixth fluid supply outlets 34 and 35 in the center of the recessed groove, Jin the second fluid flow hole that is bored in cylinder associated groove (not shown) to be provided with several.

That is, since the rotary valve member 30 is rotated together with the workpiece that the piston member 40 is moved forward or backward during the processing to bite the jaws of the chuck, the valve plate 32 and the cylinder housing 10 of the rotary valve member 30 ) Is sealed by a labyrant sealing structure in which a plurality of labyrinth parts protruding to form a space therebetween are non-contacted and engaged with each other in a labyrinth groove. When the member 30 rotates, the first fluid movement holes communicating with the third and fourth fluid supply discharge paths 23 and 24 are respectively located in at least one associated groove corresponding to the fifth and sixth fluid supply. The second fluid movement holes communicated with the discharge passages 34 and 35, respectively. Therefore, the first and second fluid supply discharge passages 12 and 13 and the fifth and sixth valves are rotated even when the rotary valve member 30 is rotated. The fluid supply discharge passages 34 and 35 communicate with each other.

On the other hand, the piston member 40 is coupled to the movement inserting portion (30a) of the rotary valve member 30 has a predetermined length of the piston rod is coupled to the valve rod (31) to move forward and backward ( 41, and the piston plate 42 which partitions and seals the cylinder chamber 33 into the front and back cylinder chambers 33a and 33b on the outer peripheral surface of this piston rod 41 protrudes.

And the cylinder chamber 33 is formed inside the front of the rotary valve member 30, the outer circumferential surface of the piston plate 42 is sealed in contact with the inner surface of the inside forming the cylinder chamber 33 is sealed cylinder The cylinder body member 50, which is divided into the front and rear cylinder chambers 33a and 33b, is fixed to the cylinder chamber 33 so that the cylinder chamber 33 is sealed.

The cylinder body member 50 has a coupling hole (50a) is formed in the body coupled to the piston rod 41 protruding in front of the piston plate 42 in a sealed state so that the piston member 40 is the cylinder chamber 33 The piston rod 41 protrudes to the front of the cylinder body member 50 so as to grip or release the jaws of the chuck connected to the piston rod 41 when moving forward by the pressure of the fluid supplied into the cylinder. It works.

Meanwhile, the rotary valve member 30 is supplied to the front and rear cylinder chambers 33a and 33b through the fifth and sixth fluid supply discharge paths 34 and 35 of the rotary valve member 30. The front and rear cylinder chamber check valves 60 and 70 are mounted to control the flow of the fluid discharged from the rear cylinder chambers 33a and 33b in one direction.

The check valve 60 for the front cylinder chamber is provided only when the fluid is supplied to the inside of the first valve housing 61 in which the first fluid passage 61a is formed in communication with the fifth fluid supply discharge passage 34. First blocking means 62 for opening the first fluid passage 61a is provided and mounted on the fifth fluid supply discharge passage 34 into the rotary valve member 30.

The first valve housing 61 is mounted on the fifth fluid supply discharge path 34 of the rotary valve member 30 as shown in FIG. 4, and communicates with the fifth fluid supply discharge path 34. And a first fluid passage 61a penetrating toward the front surface, the first base body portion 64 having a first ball seating groove 64a formed thereon;

It has a predetermined length and is coupled to the front surface of the first base body portion 64 and its end portion is coupled to the inner surface of the cylinder body member 50 through the piston plate 42 and the first fluid passage 61a therein. A first guide protrusion (63) formed at the fifth fluid supply discharge passage (34) to be connected to the front cylinder chamber (33a);

It is composed of a first pilot spool 65 which is coupled to the rear surface of the first base body portion 64 is moved by the hydraulic pressure supplied.

In addition, the first blocking means 62 for blocking the first fluid passage 61a is a spherical first ball member 62a seated in the first ball seating groove 64a of the first base body 64. Wow;

It consists of a 1st coil spring 62b which elastically supports this 1st ball member 62a inside the 1st fluid passage 61a.

That is, the first ball member 62a is elastically supported by the first coil spring 62b in a state of being seated in the first ball seating groove 64a, thereby blocking the first fluid passage 61a. .

In this state, the pressure enough to push the first ball member 62a elastically supported by the first coil spring 62b through the fifth fluid supply discharge passage 34 into the first fluid passage 61a. Only when the fluid is supplied to the first fluid passage (61a) is opened to supply the fluid to the front cylinder chamber (33a).

When the fluid is supplied to the front cylinder chamber 33a, the fluid is simultaneously supplied through the first fluid pressure passage 34a, so that the second pilot spool 75 is pushed and moved by the pressure of the supplied fluid.

The second pilot spool 75 pushes the second ball member 72a to open the second fluid passage 71a and fills the rear cylinder chamber 33b through the sixth fluid supply discharge passage 35. To drain the fluid.

On the other hand, the rear cylinder chamber check valve 70 is the fluid to be supplied to the inside of the second valve housing 71 in which the second fluid passage (71a) formed in communication with the sixth fluid supply discharge passage (35) or more than a predetermined pressure. Only when the second blocking means 72 for opening the second fluid passage (71a) is provided is mounted on the sixth fluid supply discharge passage 35 into the rotary valve member (30).

As shown in FIG. 5, the second valve housing 71 is mounted on the sixth fluid supply discharge path 35 of the rotary valve member 30, and communicates with the sixth fluid supply discharge path 35. And a second fluid passage 71a penetrating toward the front surface, and a second base body portion 74 having a second ball seating groove 74a formed thereon;

It has a predetermined length and is coupled to the front surface of the second base body portion 74 and its end portion is coupled to the inner surface of the cylinder body member 50 through the piston plate 42 and the second fluid passage 71a therein. A second guide protrusion (73) formed so as to be connected to the rear cylinder chamber (33b) in the sixth fluid supply discharge passage (35);

It is composed of a second pilot spool 75 which is coupled to the rear surface of the second base body portion 74 is moved by the hydraulic pressure supplied.

In addition, the second blocking means 72 for blocking the second fluid passage 71a is a spherical second ball member 72a seated in the second ball seating groove 74a of the second base body portion 74. Wow;

This second ball member 72a is composed of a second coil spring 72b that elastically supports the inside of the second fluid passage 71a.

That is, the second ball member 72a is elastically supported by the second coil spring 72b in a state of being seated in the second ball seating groove 74a to block the second fluid passage 71a. .

In this state, the pressure enough to push the second ball member 72a elastically supported by the second coil spring 72b through the sixth fluid supply discharge passage 35 into the second fluid passage 71a. Only when the fluid is supplied to the second fluid passage 71a is opened to supply the fluid to the front cylinder chamber (33a).

When the fluid is supplied to the rear cylinder chamber 33b, the fluid is simultaneously supplied through the second fluid pressure passage 35a, so that the first pilot spool 65 is pushed and moved by the pressure of the supplied fluid.

The first pilot spool 65 pushes the first ball member 62a to open the first fluid passage 61a and fills the front cylinder chamber 33a through the fifth fluid supply discharge passage 34. To drain the fluid.

On the other hand, when overpressure occurs in the front and rear cylinder chambers 33a and 33b in the second guide protrusion 73 of the second valve housing 71, the front and rear cylinder chambers 33a and 33b communicate with each other. Decompression means 100 for reducing the pressure in the cylinder chamber 33 is provided.

The decompression means 100 forms the first and second cylinder chamber connection passages 110 and 120 which are penetrated through the second guide protrusion 73 so as to connect the front and rear cylinder chambers 33a and 33b. The third coil spring to open the first cylinder chamber connecting passage 110 only when the fluid is pressurized to a predetermined pressure or more from the front cylinder chamber 33a to the rear cylinder chamber 33b inside the cylinder chamber connecting passage 110. And a third ball member 112 elastically supported by 111, and a predetermined pressure from the rear cylinder chamber 33b to the front cylinder chamber 33a inside the second cylinder chamber connecting passage 120. The fourth ball member 122 is elastically supported by the fourth coil spring 121 to open the second cylinder chamber connection passage 120 only when the fluid is pressurized.

That is, when the fluid is supplied to the rear cylinder chamber 33b to pressurize the piston plate 42 by the pressure of the fluid to advance the piston member 40, if excessive hydraulic pressure is applied to the rear cylinder chamber 33b, the fourth cylinder The ball member 122 is pushed by this excessive hydraulic pressure to open the second cylinder chamber connection passage 120.

When the second cylinder chamber connection passage 120 is opened, the fluid of the rear cylinder chamber 33b flows out to the front cylinder chamber 33a through the second cylinder chamber connection passage 120, and the front cylinder chamber 33a. The pressure of the rear cylinder chamber 33b is reduced while being discharged together with the fluid therein.

When the pressure of the rear cylinder chamber 33b is reduced, the fourth ball member 122 returns to its original position by the elastic restoring force of the fourth coil spring 121 to block the second cylinder chamber connection passage 120. .

When the fluid is supplied to the front cylinder chamber 33a to pressurize the piston plate 42 by the pressure of the fluid to retract the piston member 40, when the excessive hydraulic pressure is applied to the front cylinder chamber 33a, the third ball The member 112 is pushed by this excessive hydraulic pressure to open the first cylinder chamber connecting passage 110.

When the first cylinder chamber connecting passage 110 is opened, the fluid of the front cylinder chamber 33a flows out to the rear cylinder chamber 33b through the first cylinder chamber connecting passage 110, and the rear cylinder chamber 33b. The pressure in the front cylinder chamber 33a is reduced while being discharged together with the fluid therein.

When the pressure in the front cylinder chamber 33a is reduced, the third ball member 112 returns to its original position by the elastic restoring force of the third coil spring 111 to block the first cylinder chamber connection passage 110. .

On the other hand, when described in detail the operating state of the hydraulic cylinder of the present invention by the above configuration.

The first hydraulic port 10a of the cylinder housing 10 passes through the first fluid supply discharge path 12, and the third fluid supply discharge path 23 of the sleeve member 20 and the fifth of the rotary valve member 30. A first fluid passage 61a of the fluid supply discharge passage 34 and the first cylinder passage 61a of the check valve 60 for the front cylinder chamber is connected to the front cylinder chamber 33a and is connected to the third fluid supply discharge passage 23. It is connected to the check valve 70 for the rear cylinder chamber through the fluid pressure passage 34a.

The second hydraulic port 10b of the cylinder housing 10 passes through the second fluid supply discharge path 13, the fourth fluid supply discharge path 24 of the sleeve member 20, and the sixth of the rotary valve member 30. A second fluid passage 71a connected to the rear cylinder chamber 33b through a second fluid passage 71a of the check valve 70 for the rear cylinder chamber and a second fluid passage 24 connected to the fourth fluid supply discharge passage 24; It is linked to the check valve 60 for the front cylinder chamber through the fluid pressure passage (35a).

The front cylinder chamber 33a is filled with fluid with the piston member 40 retracted.

That is, when the fluid is supplied to the second hydraulic port 10b at a predetermined pressure or more, the fluid flows through the second, fourth, and sixth fluid supply discharge paths 13, 24, and 35 to the second cylinder port 10b. 2 flows into the fluid passage 71a and pushes the second ball member 72a to open the second fluid passage 71a.

Then, the fluid is supplied to the rear cylinder chamber 33b through the open second fluid passage 71a to pressurize the piston plate 42 to advance the piston member 40.

When the piston member 40 moves forward, the piston member 40 is operated to grip jaws of the chuck connected to the piston member 40 so as to firmly fix the gripped state by the pressure of the fluid.

In addition, the fluid supplied to the fourth fluid supply discharge passage 24 is supplied to the check valve passage 70 for the rear cylinder chamber through the sixth supply discharge passage 35 and to the second fluid pressure passage 35a. Then, the first pilot spool 65 of the front cylinder chamber check valve 60 is pushed and moved.

The first pilot spool 65 pushes the first ball member 62a while being pushed to open the first fluid passage 61a.

Therefore, the fluid filled in the front cylinder chamber 33a is led to the first hydraulic port 10a of the cylinder housing 10 through the fifth fluid supply discharge passage 34 through the first fluid passage 61a that is opened. It is discharged.

On the contrary, when the fluid is supplied to the first hydraulic port 10a at a predetermined pressure or more, the first ball of the check valve 60 for the front cylinder chamber through the first, third and fifth fluid supply discharge passages 12, 23, and 34. The member 62a is pushed to open the first fluid passage 61a, and fluid is supplied to the front cylinder chamber 33a through the opened first fluid passage 61a to pressurize the piston plate 42. To retract the piston member 40.

When the piston member 40 is retracted and moved, the jaws of the chuck connected to the piston member 40 are operated to grip or release the workpiece.

In addition, the fluid supplied to the third fluid supply discharge passage 23 is supplied to the check valve passage 60 for the front cylinder chamber through the fifth supply discharge passage 34 and simultaneously to the first fluid pressure passage 34a. Then, the second pilot spool 75 of the back cylinder chamber check valve 70 is pushed and moved.

The second pilot spool 75 pushes the second ball member 72a while being pushed to open the second fluid passage 71a.

Therefore, the fluid filled in the rear cylinder chamber 33b is led to the second hydraulic port 10b of the cylinder housing 10 through the sixth fluid supply discharge passage 35 through the open second fluid passage 71a. It is discharged.

As described above, when the fluid is supplied to the front and rear cylinder chambers 33a and 33b to reciprocate the piston member 40 forward and backward, the piston member 40 penetrates the piston plate 42 and is coupled thereto. The first and second guide protrusions 63 and 73 of the first and second valve housings 61 and 71 are to be moved.

When overpressure occurs while fluid is supplied to the front and rear cylinder chambers 33a and 33b, the overpressure is reduced by the decompression means 100 provided in the check valve 70 for the rear cylinder chamber. It is to prevent malfunction and deterioration of the durability of the cylinder body.

On the other hand, between the cylinder housing 10 and the sleeve member 20, between the rotary valve member 30 and the piston member 40, between the rotary valve member 30 and the cylinder body member 50, the piston plate 42 Between the outer circumferential surface and the inner surface of the cylinder body member 50 is provided with an O-ring for sealing therebetween, which is the same as the conventional configuration.

According to the configuration of the present invention described above, before the piston member is passed through the piston plates through the first and second valve housings of the check valve for the rear cylinder chamber before and after controlling the flow of fluid supplied to the front and rear cylinder chambers of the hydraulic cylinder. , There is no need to install a separate guide pin to the cylinder body or piston plate provided with the first and second guide protrusions for guiding the reciprocating motion afterwards.

In addition, the first and second valve housings of the check valves for the front and rear cylinder chambers are integrally equipped with a pressure reducing means for reducing the overpressure generated in the front and rear cylinder chambers when the hydraulic cylinder is operated. It does not need to be mounted on the piston plate.

Therefore, by reducing the number of parts installed or installed in the hydraulic cylinder to enable a compact design of the hydraulic cylinder, as well as to reduce the manufacturing cost, it is a very useful design that can increase the assembly during manufacturing.

Claims (2)

A through part 11 penetrates from one side to a predetermined size is formed, and the first and second fluid supply discharge paths 12 and 13 through which fluid flows into and out of the through part 11 are formed from the outside of the body. A formed cylinder housing 10; Coupling portion 21 is formed through the inner side of the body from one side to the other side, the third body connected to the first, second fluid supply discharge passage (12, 13) from the outside of the body to the inside of the coupling portion 21 A sleeve member 20 having four fluid supply discharge paths 23 and 24 formed therein and fixedly coupled to the through part 11 of the cylinder housing 10; One side is composed of a valve rod 31 coupled to the engaging portion 21 of the sleeve member 20, the other side is composed of a valve plate 32 located on the front of the cylinder housing 10, the valve plate ( 32) Fifth and sixth fluid supply discharge paths 34, which form a cylinder chamber 33 in front, and connect the third and fourth fluid supply discharge paths 23 and 24 to the cylinder chamber 33 therein. A rotary valve member 30 formed with 35; The body is composed of a piston rod 41 coupled to the valve rod 31 having a predetermined length and sliding forward and backward, and the cylinder cylinder 33 on the outer circumferential surface of the piston rod 41, the front and rear cylinders A piston member (40) protruding from the piston plate (42) for partitioning and sealing the seals (33a, 33b); It is mounted on the valve plate 32 front of the rotary valve member 30 to supply fluid therein and forms a cylinder chamber 33 partitioned into the front and rear cylinder chambers 33a and 33b by the piston plate 42. A cylinder body member 50 which seals the cylinder chamber 33; The first fluid passage 61a is opened only when the fluid is supplied to the inside of the first valve housing 61 having the first fluid passage 61a communicating with the fifth fluid supply discharge passage 34. A check valve (60) for a front cylinder chamber provided with a first shut-off means (62) and mounted on the fifth fluid supply discharge path (34) into the rotary valve member (30); The second fluid passage 71a is opened only when the fluid is supplied above a predetermined pressure in the second valve housing 71 in which the second fluid passage 71a communicating with the sixth fluid supply discharge passage 35 is formed. In the hydraulic cylinder comprising a check valve 70 for the rear cylinder chamber is provided with a second blocking means 72 is mounted on the sixth fluid supply discharge path 35 into the rotary valve member 30, The first valve housing 61 of the check valve 60 for the front cylinder chamber is formed with a first fluid passage 61a for connecting the fifth fluid supply discharge passage 34 to the front cylinder chamber 33a. It has a first guide protrusion (63) protruding with a predetermined length so that the end portion penetrates through the piston plate (42) of the piston member (40) and is coupled to the inner surface of the cylinder body member (50). The second valve housing 71 of the check valve 70 has a second fluid passage 71a which connects the sixth fluid fluid supply discharge passage 35 to the rear cylinder chamber 33b, and has an end portion of the piston. And a second guide protrusion 73 extending through the piston plate 42 of the member 40 and having a predetermined length so as to be coupled to the inner surface of the cylinder body member 50. The second guide protrusion 73 If overpressure occurs in the front and rear cylinder chambers 33a and 33b, the front and rear cylinder chambers 33a, A hydraulic cylinder, characterized in that the decompression means (100) is provided to communicate with 33b) to reduce the pressure in the overpressured cylinder chamber (33). The first and second cylinder chamber connection passages 110 and 120 of claim 1, wherein the decompression means 100 penetrates through the second guide protrusions 73 to connect the front and rear cylinder chambers 33a and 33b. ) And the first cylinder chamber connection passage 110 only when the fluid is pressurized to a predetermined pressure or more from the front cylinder chamber 33a to the rear cylinder chamber 33b inside the first cylinder chamber connection passage 110. ) Is provided with a third ball member 112 elastically supported by the third coil spring (111), the front of the rear cylinder chamber (33b) in the interior of the second cylinder chamber connecting passage (120) The fourth ball member 122 elastically supported by the fourth coil spring 121 to open the second cylinder chamber connecting passage 120 only when the fluid is pressurized to the cylinder chamber 33a by a predetermined pressure or more. Hydraulic cylinder, characterized in that made up.